While this is an old post, I've been looking at different solutions to this problem and thought I'd post the workaround I've decided to use. Hopefully, this might save others a headache in getting their drop-down menus to work.
I had this problem in IE where horizontal drop-down menus were hidden behind a Flash banner that was placed immediately beneath the menu.
Here is the markup I've used to add a Flash banner in my HTML page:
Code:
<object type="application/x-shockwave-flash" data="mymovie.swf" width="880" height="136">
<param name="movie" value="mymovie.swf" />
<param name="wmode" value="transparent" />
<param name="quality" value="high" />
<img src="myaltimage.jpg" alt="My alt text" width="880" height="136" />
</object>
This line helps to get the drop-down menus to sit over the top of the Flash banner in IE:
Code:
<param name="wmode" value="transparent" />
While there is a recommended method to embed Flash, personally I've found the above markup to be the simplest. It passes validation and you can add alternative content (I used a static image in the markup for users without the Flash Player or have Flash disabled in their browser).